Under Armour Men's Mk-1 Active Shorts - Lightweight and Breathable

Our review of the Under Armour Men's Mk-1 Shorts finds them to be an excellent choice for men who want a lightweight, breathable short for training, warm ups, and post-game wear. The single biggest reason to buy is the fabric performance: the stretchy knit blends a fast-drying polyester with elastane for true four-way stretch and efficient moisture wicking, so the shorts stay comfortable during high-movement sessions. These feel intentionally minimal yet durable, making them a versatile daily training short rather than a heavy, structured athletic short.

Key Features

• Stretchy knit fabric: Provides a barely-there feel while allowing full range of motion for dynamic drills and casual wear.
• Moisture-wicking material: Dries quickly after sweat, helping the wearer stay cool and reducing chafing during long workouts.
• 4-way stretch construction: Moves with the body in every direction so lunges, sprints, and lateral movements feel unrestricted.
• Mesh side panels: Add targeted ventilation to keep airflow moving across the hips and upper thighs in warm conditions.
• Encased waistband with drawcord: Offers an adjustable fit that stays put in motion without adding bulk.
• Open hand pockets: Provide quick storage for small essentials while keeping the short lightweight since there is no liner.

Who It's For

The Mk-1 Shorts suit active men who prioritize lightweight performance and freedom of movement for gym sessions, practice, or casual athletic wear. Runners who prefer a simple short without a liner, gym-goers who value breathability, and anyone wanting a fast-drying option for warmups will appreciate the fabric and ventilation.

Those who need built-in compression or a liner for support or modesty should look elsewhere, and athletes wanting multiple pockets or a longer inseam should consider other models. The Mk-1 is best as a comfortable, do-it-all training short rather than a technical race or trail short.

Pros & Cons

Pros

• Extremely lightweight and comfortable for extended wear.
• Effective moisture wicking and quick drying during sweat-heavy activity.
• Four-way stretch and mesh panels improve mobility and ventilation.
• Simple, adjustable fit with an encased waistband and internal drawcord.

Cons

• No liner included, so some users may prefer a short with built-in support.
• Limited pocketing for those who carry multiple items while training.

Specifications

Brand	Under Armour
Fabric	90% Polyester / 10% Elastane
Inseam	7 in
Pockets	Open hand pockets
Liner	No liner
Waist	Encased elastic with internal drawcord

Our Verdict

The Under Armour Mk-1 Shorts are a smart buy for anyone who wants a light, breathable training short that moves with the body and handles sweat well. They deliver strong fabric performance and ventilation at a good value, but those needing a liner or extra storage should consider alternatives.

Frequently Asked Questions

Do these shorts have a liner?
The Mk-1 Shorts do not include a liner; they are designed as a lightweight outer short.

How long is the inseam?
These shorts have a 7 in inseam, offering moderate coverage for most training activities.

Are they suitable for hot weather?
Yes, the stretchy knit fabric with mesh side panels and moisture-wicking construction makes them well suited for warm conditions.